Thermostatic cut-off valve



Filed May 24, 1928 .N mw n f mw m w@ m RW m hv; H .J w f w- 1 A l Y anw/ m, B I Wm ,m nn M Y w" iw ML" Patented Dec. S, 1931 STATES PATENT orrics LUTHER D. LOVEKIN, OF WYNNEWOOD, PENNSYLVANIA, ASSIGNOR T KITSON COM- THERMOSTATIC CUT-OFF VALVE Application filed May 24,

The general object of the present invention is to provide a thermostatic valve specially devised for use in connection with fiuid heaters and in particular domestic water heaters and adapted to cut olf the supply of fuel to the heater burner when the temperature in the heater attains a predetermined maximum.

My improved valve is intended for use as 1o a safety or cut-off device, and not as a therinostatic temperature regulator, and is characterized by the special provisions made for subjecting a fusible metal part employed in the valve mechanism to the temperature of the liquid in the heater with which the valve is used without exposing said part to contact with the water. To this end I provide a casing body with a shank extension which is adapted to extend into a heater tank, and

I mount said fusible part within the portion of said extension located within the heater tank.

A preferred form of my improved valve is further characterized by features of construction and arrangement adapting the valve to be connected to a heater tank structure through its hot `water outlet pipe, or other pipe connection, so that the valve may be applied to existing types of heaters not initially designed for use with such a valve at a minimum of cost and trouble in applying the valve. For this purpose I form the shaft extension of my improved valve so that it may be readily secured in a T form-V ing a part of the hot water outlet or other heater pipe connection, and so that it coinprises a slender portion adapted to pass into the body of the heater through the T and through the nipple connecting the latter to the heater tank.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For

a better understanding of the invention, however, and the advantages possessed by it reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described preferred embodiments of my invention.

1928. Serial No. 280,192.

Of the drawings :f-

Fig. 1 is a sectional elevation of the cutolf valve and part of the heater shown in Fg2s Fig 2 is an elevation of a water heater and its improved cut-off valve; and

Fig. 3 is a sectional view of a portion of a valve of modified form.

In the drawings and referring first to Fig. 2, A represents a conventionally illustrated automatic water heater having a hot water outlet B and heated by fuel supplied to a burner (not shown) through a fuel supply pipe C. In the construction shown in Fig. 2, the supply of gas through the pipe C to 55 the burner is normally regulated by a thermostatic valve D, which may be of any usual form for decreasing or increasing the fuel supply as the temperature of the water in the boiler increases to, or falls below a predetermined value.

In accordance with the present invention the supply of gas through the pipe C is also controlled by an automatic shut-oft7 valve E. The valve E comprises a casing body having formed in it a passageway comprising an inlet chamber portion E and an outlet chamber portion E2 separated by a partition in which is formed a valve seated port E3. Flow through the port E3 is controlled by a 80 valve F. As shown, the valve Fis formed with a cylindrical extension F slidingly received in and guided by a housing part Gr shown as threaded linto an aperture in the valve casing body in line with the port E3.

The valve F is arranged to have a loaded or valve closing tendency which is due, in the construction shown in Figsjl and 2, in part to gravity, and in part to the action of a spring H mounted in the housing G r. In the arrangement shown in Figs. l and 2, this valve closing tendency is normally opposed, and the valve is held in its open position by v means comprising a fusible metal abutment I and a strut formed in part by a stem portion F2 of the valve F, and in part by a rod .I in line with the valve stem F2 and interposed between the latter and the fusible abutment I. The fusible abutment I is located in a hollow shank extension of the valve casing. As

shown, this shank extension comprises an integral tubular extension E4 of the valve casing body, a tubular part K, and a tubular abutment receiving member L. Advantageously, and as shown, the member K is in the form of a tube having eXternallv threaded ends, one of which is screwed into a threaded socket formed in the end of the valve casing shank extension E4, and the other end of which is threaded into the member L which is in the form of an internally threaded sleeve. The end of the sleeve L remote from the valve casing is closed, in the construction shown in Fig. l, by a plug M having a tubular externally threaded portion Which is screwed into the sleeve L. The fusible abutment I is in the form of a disc of fusible metal having the desired melting point and is shown in Fig. l as bearing at its margin against the adjacent end of the tubular portion of the plug M.

As shown, the pipe connection to the outlet B comprises a T or fitting part B having a through passage coaxial with the outlet B and communicating With the latter through a nipple B2, and having a lateral outlet B3 to which the hot Water service pipe B4 is connected. As shown, the end of the shank extension portion E4 of the valve casing body is externally threaded and is screwed into the upper end of the through passage in the T fitting B', and the tubular portion K of the casing extension extends axially through the T fitting B and through the nipple B2 into the heater tank A. The fusible metal abutment I may thus be located tivo or three inches or so below the top Wall of the tank, so as to be directly responsive to the temperature of the Water in the tank, and practically free from any direct cooling effect due to heat radiation from the tank Wall or fitting parts or to gas flow through the valve thoroughfare.

It Will be observed that the parts M, L, K and E4 unite to form an extension of the valve casing body comprising a chamber space communicating at one end With the passageway through the valve casing body, but closed at its other end and that this space receives the fusible metal abutment I, and the major portion of the strut formed by the valve stein F 2 and rod J. To guard against any objectionable collection of tar condensing out of the fuel gas in the lower portion of the chamber space in the shank extension, a Washer E", fitting closely about the valve stem F 2, is mounted in the valve casing between the outlet passage E2 and the space in the chamber shank extension of the valve casing. i

IVi th the described construction. the fusible metal abutment I is located Within the tank body so as to be directly responsive to the temperature of the Water in the heater tank. If, through a failure of the thermostatic valve D, or for any other cause, the heater Water temperature rises to the maximum fixed by the composition of the abutment I, the latter softens and the closing tendency of the valve F due in the construction sh ivn, as previously explained, in part to gravity and in part to the spring H, causes the valve to close. If the valve closing tendency is made as great as I consider ordinarily preferable, the va vvill ordinarily seat before the disc I me ls.

In such case the rod J iunches a plus' out of small consequence, since the plug M may be easily separated from the sleeve L iv n the cut-oliz valve is removed, as is necesi-:ary in any event for the replacement of the fusible metal disc I. Vsrficn the )hnT M removed the rod J, if anchored to the plug, may be loosened, and the fusible metal in contact with the plug M or rod J may readily be eliminated by heating the parts in a` gas llame, or otherwise, to the temperature required to melt the metal employed in the disc I.

As will be readily apparent, With the mechanism shovvn in F igs. l and 2 the fusible metal abutment I, While out of contact with the Water in the tank or boiler with which it is associated, is so disposed that it is n' tained at approximately the same .iture as the Water, nd is not subjected to any si0nicant coolingY either by radiation from the external portions of the valve mechanism or the litting in which it is mounted, or by 10 the cooling effect of the fuel flow thin-ugh the valve thoroughfare.

The valveconstruction shown in l" and 2, obviously may be readily connect s. 'l to an existing' Water tank or boiler installation 11e not initially devised with intent for such use, since such installations ordinarily comprise pipe connections to the tank or boiler similar in character to those formed by the pipe litting` parts B, B2 and B4'. sion portion K may well consist of a section of ordinary tubingof an` external diameter of a half an inch or so, which small enough to pass through the T B and nipple B2 witlout objeotionably obstructing the Aflow of iva- 12e ter therethrough. It the application of the type of valve mechanism shown in F l to different installations, or to different types of tanks or boilers requires the use of shank extensions of different lengths, such length vferi- 1S i ations may be provided Without other chan in the apparatus than suitable variations in the lengths of the tube sections K and rods J employed.

Where circumstances permit the use of a '1f-I The shank extenll cut-orf valve having' its shank extension -hreadeddirectly into an aperture in the tank or boiler wall with a portion of the shank extension projecting into the tank or boiler, I may advantageously employ the form of my invention shown in Fig.

The casing of the valve EA shown in Fig. 3 differs .from that of the valve shown in Figs. l and 2, in that the entire shank extension is formed by an integral hollow eXtension portion E40 of the valve body. The end of the bore of the shank extension is closed by a screw plug MA, which may be brazed in place, since in this form of 'my invention the fusible metal abutment I may be replaced without removing the plug MA. As shown, the shank extension E40 has an intermediate externally threaded portion screwed into a threaded opening in the wall AA of the tank or boiler with which the valve is used, and is so proportioned that the fusible abutment I is located at a suitable distance from the wall AA at the inner side of the latter.

In the valve shown in Fig. 3, the fusible metal disc I is mounted in a cartridge-like casing comprising a cup-shaped body member O, and a gland-like member P threaded in place in the otherwise open end of the member O and forming a guide for a strut member JA in the form of a rod having a head J at its outer end, which is normally engaged, within the outlet chamber E2 of the valve EA, by the aligned stem F2 of the cut off valve member. The member O is formed intermediate its ends with an internal circumferential shoulder against which the disc I bears at its edge. The adjacentrend of the rod JA bears against the center of the abutment disc I. As shown, the member J is also guided intermediate its ends by a washer Q, and is guided adjacent its upper end by a washer member E5.

The diameter of the valve controlled port is made greater than the external diameters of the washer members E5 and R and cartridge casing parts O and P. In consequence, when the melting or perforation of the abutment member I makes the replacement of the latter necessary, such replacement may be effected by removing the control valve from the valve casing EA, and then withdrawing the rod J from the valve casing through the port E3. The head J on the upper end of the rod JA facilitates the with drawal of the latter. A pin R passing through the rod JA beneath the top of the gland member P prevents the cartridge casing fo-r the abutment I from separating from the rod JA when the latter is being removed. Similar pins R may extend through the rod JA beneath the washers E5 and R, though this is not essential, since the removal of the rod JA and cartridge casing parts O and R, necessarily effects the removal of the washers Q and E5.

While in accordance with the provisions of the statutes, I have illustrated and described the best form of embodiment of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention as set forth in the appended claims and that in some cases certain features of my invention may be used to advantage without a corresponding use of other features.

Having now described my invention what I claim as new and desire to secure by Letters Patent ist- 1. The combination with a fluid fuel burning water heater and its fuel supply connection, of a pipe connection to the heater comprising a T and a nipple through which one end of the through passage of the T opens to the water space of the heater, a fuel cut off valve comprising a valve casing body portion and a hollow shank, the latter being attached to said VT and comprising a slender portion extending through said through pas sage into the heater water space, said casing body portion being formed with a passageway forminga part of said fuel supply connection, a valve controlling said passageway and tending to move from an open position into a position inwhich it closes said passageway, and means normally holding said valve in its open position comprising a fusible metal abutment mounted in a portion of said shank located within the water space and strut means extending between said abutment and said valve.

2. In combination with a valve casing which comprises a body portion formed with a passageway through it, and a shank eX- tension from said body portion with a passage therein extending from the end of said shank remote from the body portion to said passageway, a part detachably secured to said shank end and normally closing the corresponding end of said passage, a valve controllingV said passageway and tending to move from an open position into a position in which it closes said passageway, Vmeans normally holding said valve in its open position comprising a fusible abutment mounted in said passage adjacent its said end and strut means extending between said abutment and said valve, said strut means comprising a section insertible with said abutment into said shank through the said end of the latter when said detachable part is removed.

3. In combination with a valve casing which comprises a body portion formed with a passageway through it and a shank extension from said'body portion with a passage therein extending from the end of said shank remote from the body portion to said passageway, a part detachably secured to said shank end and normally closing the corresponding end of said passage and formed with a cavity opening to said passage, a valve controlling said passageway and tending to more from an open position into a position in which it closes said passageway, means normally l'iolding said valve in its open position comprising a fusible abutment engaging said part at the margin of said cavity, and strut means extending between said abutment and said valve and comprising a section separable from said valve member and adapted to enter said cavity when said abutment softens and permits such entrance.

4. In combination with a valve casing which comprises a body portion formed with a passageway through it and a shank extension from said body portion with a passage therein extending from the end of said shank remote from the body portion to said passageway, said shank comprising aligned sections threaded together, of which the end section is in the form of an internally threaded sleeve, the section adjacent thereto is in the form of a tube having one end threaded into said sleeve, and. a section more closely adjacent to said body portion is in threaded engagement with the other end of said tube and has an externally threaded portion larger in external diameter than said sleeve, a plug threaded into the second end of said sleeve, a valve controlling said passageway, and means normally holding said valve in its open position comprising a fusible abutment mounted in said sleeve and supported by said plug, and strut means extending between said abutment and said valve and comprising a sec- Y tion separable from the valve and insertible in and removable from said shank through the said end of the latter when said plug is removed.

5. In combination with a valve casing which comprises a body portion formed with a passageway through it and a shank extension from said body portion with a passage therein extending from the end of said shank remote from the body portion to said passageway, said shank comprising two aligned sections of which the one more remote from said body portion is smaller in external diameter than thev other of said sections, means connected to the end of said more remote section most remote from said body portion for closing the corresponding end ofsaidpassage, a valve controlling said passageway, a fusible abutment mounted in said passage and supported by said means, and strut means tending between said abutment and said valve and holding said valve in its open position.

6. In combination with a valve casing which comprises a body portion and a hollow shank and is constructed for attachment to the wall of a tank with a tank-entering portion of said shank projecting into the tank through an aperture in said wall, said casing being formed with a passageway in said body CII 

